Locks for sterilization containers have already been known for years and are used to connect the container cover and the usually box-like bottom part of the sterilization container to one another detachably and tightly. In order to achieve as firm a hold of the container cover on the bottom part, locks of a lever-like design are used, among other things, which comprise a plurality of components, which can be caused to lockingly mesh with one another in the closed state. Another variant of locks operates according to the “toggle lever” principle, and such locks may be provided with a rocker arm and a clamping strap in the manner of a quick-acting lock.
A lock, which operates according to the “locking principle,” is known from DE 197 55 532 A1. Furthermore, such locks are generally dealt with in that document. Thus, it is explained that the clamping together of the container cover and of the bottom part can be made possible by special locks, which have a pivotably mounted closing flap on one part (container cover or bottom part) and a stationarily fixed detent on the respective other part. The detent may be elastically deformable, so that a locking projection of the closing flap can snap into a locking recess of the detent during the pivoting motion of said closing flap. The detent is elastically deformed during the pivoting motion such that the locking projection can “slide into” the locking recess. The necessary tensioning force for bracing the container cover against the bottom part is determined by the elasticity of the detent.
Since certain difficulties arise in such constructions in connection with the compensation of manufacturing tolerances and the adaptation of the necessary tensioning force between the container cover and bottom part, it is proposed in the subject of DE 197 55 532 A1 that the locking projection in the flap be designed such that it is elastically displaceable in the closing flap. Corresponding to the dimensions of the closing flap, a relatively great path of displacement is available, which is substantially greater than the path of displacement of an elastically deformable detent. Adaptation to manufacturing tolerances is facilitated by this “enlarged” path of displacement. Furthermore, it is possible to vary the spring force with which the locking projection is displaced in the direction of the rebound.
If the locking projection is made in one piece with the closing flap, the elastic displaceability is achieved by elastically deformable connection members, which may be designed, for example, as spring-like webs or the like, being arranged in the connection area between the locking projection and the closing flap. Provisions are made in a preferred embodiment for the locking projection to be designed as a locking body, which is separate from the closing flap and is mounted displaceably in the flap in a guide. This embodiment is said to have the advantage of being able to be manufactured in an especially simple manner.
If was found in practice for such a lock that this is subject to increased wear because of the locking connection and also that the spring forces of the spring elements used weaken during a longer operating time, so that there is a risk that the container cover will be lifted off from the bottom part under higher internal pressures.
Furthermore, such locking locks are also known from U.S. Pat. No. 4,331,251 A. One of the locking elements, which can be caused to lockingly mesh with one another, is arranged elastically in a spring-loaded manner, for example, at the bottom part of the sterilization container, in this case as well. A hinged bolt, which is likewise provided with a detent, can extend lockingly behind this [the sterilization container], so that the sterilization container is thus closed.
A locking lock, which is designed as a “snap lock,”, is known, in turn, from DE 721 588 C. A pivotable strap, which has an arc-shaped strap section, is provided in this construction. This strap section can be caused to lockingly engage a locking depression, for example, of the bottom part of the sterilization container.
Since such sterilization containers must be tight when the container cover is attached, the elastically resilient components must be designed as extremely stable components in the locking variants, so that the components that can be brought into locking connection with one another are subject to extremely great wear. If the locking forces that maintain the two components lockingly in connection with one another are too weak, there is a risk that the container cover is lifted off from the bottom part during the sterilization process and tightness is thus no longer guaranteed.
Furthermore, locks operating according to the toggle lever principle and above dead center principle are also known from the state of the art. A tensioning lever, which is mounted pivotably by means of a corresponding mount, for example, at the bottom part of the sterilization container, is provided in these locks. A tensioning strap is mounted pivotably at the tensioning lever at a certain distance from the mounting axis. When opening the tensioning lever, this clamping strap is moving away from the mounting axis of the tensioning lever and can thus be manually hung into a draw hook, which is in turn arranged fixed at the container cover. This draw hook is pulled during the closing operation in the direction of said mounting axis by the clamping strap due to the eccentric mounting of said clamping strap in relation to the mounting axis of the tensioning lever, so that the container cover can be braced against the bottom part. The pivot axis of the clamping strap according to the “above-dead-center principle” therefore lies in the fully closed state of the tensioning lever at the container wall of the bottom part as the mounting axis of the tensioning lever, so that independent opening of the tensioning lever is not possible.
The handling of such “classic” toggle lever locks is somewhat cumbersome, because the clamping strap freely movable at the tensioning lever must always be caused to mesh with the draw hook manually, especially for closing.
Further, various embodiment variants of container locks, which operate according to the above-dead-center principle, are known from U.S. Pat. No. 4,915,913 A. A tensioning lever, which is arranged pivotably at the container housing, is provided in one of these variants. A closing flap is arranged rotatably at the container cover. At its movable end, the closing flap has an end section bent off approximately semicylindrically towards the tensioning lever. The tensioning lever is provided with an opening, whose upper limiting edge directed in the closed state towards the closing flap has a likewise somewhat semicylindrically shaped meshing section. In the closed state, the end section of the closing flap passes through the tensioning lever and is in pulling connection with the meshing section of the tensioning lever. The positive-locking connection between the end edge of the closing flap and the meshing section of the tensioning lever is at a shorter distance in this closed state from the outer wall of the container housing than the axis of rotation of the closing flap and the pivot axis of the tensioning lever, so that a torque, which holds the tensioning lever and hence the container lock in the closed position, acts on the tensioning lever according to the above-dead-center principle. To open this lock, provisions are made for the tensioning lever to be deflected manually from its closed pivoted position. At the same time, a rotary motion of the closing flap is brought about by the pivoting motion of the tensioning lever brought about thereby via the positive-locking connection between the end section of the closing flap and the meshing section of the tensioning lever. The tensioning lever with its opening is moving during this pivoting motion of the tensioning lever along the closing flap, so that the latter passes through the opening over up to about half of its entire length. The closing flap is in contact with the meshing section of the tensioning lever in this opened position of the opening and is located with its end section under the meshing section. The meshing section and end section do not mesh with one another any longer in this position of the closing flap and tensioning lever. However, to make it nevertheless possible to lift off the container cover from the container housing, the closing flap must be brought manually from this half-opened position into a more widely opened position, while the tensioning lever must be maintained at the same time in its opened position. The adjusting motion of the closing flap is limited now by the opening of the tensioning lever. If the closing flap is in its maximally opened position, the tensioning lever must now be brought again into its closed position, so that the closing flap becomes unmeshed from the opening of the tensioning lever. It is only now that the container cover can be removed from the container housing. It can be seen that handling is extremely complicated in the case of this lock.